Okay so this line is written in the booklet itself, because of that this line is part of the lyrics and I assume has a meaning. But I don't know what this line/words mean or what it refers to. And there is this too

たらりりら

たららりら

らりどう

永く絶えずおはしませよ

What I have in mind is this is onomatopoeia for something or a line that refer to something or a word that I don't know.

P.S. since I don't think I can post the full lyrics of the song, the language used in the song is more traditional and the song itself is like a wishes(long life and good health) to everyone rather than nowadays song/pop songs(hope that helps a little)

This play is traditionally performed as a ritual that commemorates "the origin of Noh" rather than an ordinary play. Due to its ancient and obscure background, the bolded part of script has been known to scholars as incomprehensible, mysterious phrases.

There are theories claim that it could be "shouted out melody", "onomatopoeia", "Buddist incantation", "Korean phrase", or even "Tibetan phrase", but generally considered too corrupted to reasonably reconstruct. So in today's perspective, it is nothing more than meaningless chant or spell.